Work engagement is a result of a multitude of different factors and dynamic processes. In general, interaction and the experience of belonging to a community, trust, support and helping others, personal development, commitment, and motivation affect work engagement. These factors can be studied from different perspectives and in relation to different actors—managers, employees, groups, and organizations. This chapter focuses on manifestations of work engagement, and on a desire to develop as an engagement manifestation based on research in the Finnish Air Force Academy. Development can focus on the employee ‘s own competence, work, the organization’s processes or products, or any other work-related matter. The manager’s response to employees’ need for developing their skills is a leadership act which affects engagement: while the need for developing one’s skills is an expression of engagement from the point of view of an employee, the manager’s actions strengthen or weaken engagement.